Containers typically include a neck finish having helical threads for receiving a closure, lid, or cap. U.S. patents that illustrate containers of this type include U.S. Pat. No. 2,589,005 titled “Glass Container” (hereafter, the '005 patent). The '005 patent describes a screw-threaded neck portion, more specifically, it describes a spiral screw thread having substantially greater length than the circumference of the neck.
Another type of container may include a neck finish including three or more locking lugs, each having circumferentially extending cam portions, and stop portions extending axially from the cam portions and including ramp portions all extending at the same angle. Typically, the lugs circumferentially overlap one another, a first parting line of the neck finish intersects a straight portion of one of the locking lugs, and a second parting line is spaced between circumferential ends of adjacent lugs. Usually, one of the adjacent lugs has a circumferentially truncated ramp portion with a circumferential edge that is spaced at least fifteen angular degrees from the second parting line to provide clearance for opening and closing of neck ring equipment used to form the neck finish. Such locking lug designs can be susceptible to cross threading of a closure on the neck finish.
A general object of the present disclosure, in accordance with one aspect of the disclosure, is to provide a neck finish for a container that minimizes the likelihood of cross threading a closure thereto.
The present disclosure embodies a number of aspects that can be implemented separately from or in combination with each other.
A container neck finish in accordance with one aspect of the disclosure includes a generally cylindrical outer surface, an axially facing sealing surface, a circumferentially continuous bead projecting radially outwardly from the outer surface and axially spaced from the sealing surface, and at least three circumferentially spaced retention elements projecting radially outwardly from the outer surface, and being located axially between the sealing surface and the bead. The retention elements include only one first retention element including a first cam portion extending circumferentially, spaced axially from the sealing surface at a first level, and intersected by a first parting line, an upturned portion extending from a first end of the cam portion, and a first stop portion extending from a second end of the cam portion and including a first ramp portion extending to the bead. The retention elements also include two or more additional retention elements including a second retention element and a third retention element, each including a second cam portion extending circumferentially, and spaced axially from the sealing surface at the first level, a venting portion axially spaced from the bead at a second level different from the first level, and having a circumferentially extending retention portion, a downturned end at a first end of the venting portion, and a connecting portion extending between the retention portion and the cam portion, and a second stop portion extending from a second end of the second cam portion and including a ramp portion extending to the bead. The ramp portion of the third retention element is spaced less than ten angular degrees from a second parting line and there is no circumferential overlap of the retention elements.
In accordance with another aspect of the disclosure, there is provided a container neck finish that includes a generally cylindrical outer surface, an axially facing sealing surface, a bead projecting radially outwardly from the outer surface and axially spaced from the sealing surface, and at least three circumferentially spaced retention elements projecting radially outwardly from the outer surface, and being located axially between the sealing surface and the bead. The retention elements include a first retention element including a first cam portion, a upturned portion extending from a first end of the cam portion, and a first stop portion extending from a second end of the cam portion and including a first ramp portion extending to the bead. The retention elements also include a second and a third retention element, each of the retention elements including a second cam portion axially spaced from the bead, a venting portion axially spaced from the second cam portion toward the axially facing sealing surface, and a second stop portion that includes a ramp portion extending to the bead. The ramp portion of the third retention element includes a ramp outer surface that extends from the stop portion and radially decreases and converges to the neck finish outer surface, wherein the intersection between the ramp outer surface and the neck finish outer surface is within ten angular degrees of a parting line on the neck finish.
In accordance with another aspect of the disclosure, there is provided a container neck finish that includes an outer surface of the neck finish having a parting line, an axially facing sealing surface, a bead projecting radially outwardly from the outer surface and axially spaced from the sealing surface, and a plurality of circumferentially spaced retention elements projecting radially outwardly from the outer surface, and being located axially between the sealing surface and the bead. At least one of the retention elements includes a stop portion including a ramp portion that extends circumferentially toward the parting line and radially inwardly toward the neck finish outer surface and converges therewith at a location within ten angular degrees of the parting line.